The synthesis and liquid crystalline (LC) behavior of LC3-and

N

-substituted polypyrroles

a new type of conducting LC polymer

are summarized systematically. It is pointed out that LC polypyrrole derivatives can be obtained through chemically oxidative polymerization

electrochemically oxidative polymerization and dehalogen polycondensation. They all possess thermotropic LC behavior

most of them show smectic LC phase

and a few of them show nematic LC phase. Some of them show two types of smectic LC phases and some of them show monotropic LC phase. The polypyrroles having the LC mesogens on

N

-substituted position exhibit more stable LC state than those having the LC mesogens on3-substituted position. Long methylene spacers and polar LC side chain can form large LC domains and then give stable LC state. Uniaxial orientation of LC

N

-substituted polypyrrole can be formed by a friction technique. It is hopeful that the big intractability of the processing and formation of the polypyrrole could be overcome because of the successful preparation of polypyrrole derivatives exhibiting thermotropic liquid crystallinity.